Chain-link construction



March 4 1924. 1,485,520

E. B. NICHOLS CHA'IN LINK CONSTRUCTION Filed March 25, 192c INVENTLQYR:

Patented Mar. 4, 1924.

EDGAR B. NICHOLS, OF ROCHESTER, NEW YORK.

' CHAIN-LINK CONSTRUCTION.

Application filed March-25,

To all whom it may concern:

Be it known that I, EDGAR B. NIoHoLs, a citizen of the United States, and a resident of Rochester, county of Monroe, and State of New York, have invented a certain new and useful Improvement in Chain-Link Constructions; and I do hereby declare that the following is a full, clear, and exact de scription thereof, reference being had to the accompanying drawings, in which like numerals refer to like parts.

This invention relates to links for drive chains and the method of forming same, and is an improvement over my former application filed April 1, 1918, Serial No. 225,- 998.

The prime feature of this invention is in forming the link from a strip or bar of metal, which strip is given a multiplicity of folds and so arranged as to form pin openings at the ends of the links so formed.

One object of the present invention is to provide a construction whereby accuracy and uniformity of spacing between pin bearings may be obtained, accuracy being an essential condition in a drive chain. Another object is to assure an even bearing on the pins or rivets for the full width of the link. A further feature of the invention is the provision for securing the ends and overlapping portions of the link together.

In the manufacture of drive chain, it is customary to punch or shear the link by means of suitable dies, from bar metal or to mill it from stock rolled into the special form desired, or cast of suitable metal, usually malleable iron, of a thickness equal to the required width of the link. As the stresses in the chain are not parallel to the maximum fiber strength of the piece when so made, it is necessary to make the links from high grade steel or cast them separately in molds. Both of these methods are very expensive. 7

The principal defect in the usual method of manufacture, however, is due to the fact that in the punching or shearing of the link, a burr orbreakout edge is left in each pinhole and around the edges of the link so that only a small area can actually make contact with the pins or rivets. This surface not being parallel to the rivet, soon wears and when the chain is in service, the pin bearing becomes an elongated hole.

1920. Serial No. 368,678.

Thus, the length of the link between pin centers is materially increased, so that the chain is, in effect, stretched,and' will not function properly with the sprockets or gears.

In the invention set forth herewith, the link is formed of a thin metal strip, bar, or ribbon, which is folded or doubled upon itself either once or a number of times to form pin openings, and. also, if desired, to 1;.

form lugs or offsets of various shapes. The strip or bar when rolled or drawn, is of uniform cross section throughout, the greatest tensile strength being lengthwise,or parallel to the fibres of the metal, and the folds being widthwise, or transverse to the course of the fibres. The metal may therefore be of low grade. as compared to that required for punched or sheared links.

To these, and other ends, the invention consists in the various constructions and arrangements set forth in the following specification, and illustrated in the drawings in which- Fig. 1, is a perspective view of a chain link, constructed in accordance with, and

illustrating, one form of my invention; and

Fig. 2, is a perspective view of another embodiment of my invention.

My invention comprises forming a link of fiat metal by bending the thin strip widthwise into a plurality of overlapping folds to form a link with pin openings at each end. I prefer to have the medial portion of the link-'that part lying between the pin openin-gsof a greater thickness of metal than the pin. openings, and consequently, as shown in Figures 1 and 2, have the ends of the metal strip in overlapping relation.

Under ordinary conditions the folds of the strip of metal will serve to hold the links in proper shape, but when the links are subjected to heavy strain the medial portion of'the link may be permanently secured as by brazing, soldering or welding.

The last mentioned method has proved most this portion, 6, can be rolled after the metal folds are permanently united at their medial contacting portions. In Figure 2, a diiierent form of attachment carrier 64 is shown, being, like portion 6, formed of an integral portion of the metal from which the link is made.

By forming the links in the manner herein shown, they may be very cheaply constructed and yet rendered extremely strong and durable. The grain or [ibre of the bars of metal runs longitudinally thereof, so that the fibre will extend lengthwise around the pins at the ends of the link, greatly increasing its strength.

As there is no punching or shearing of the strip, no angular surface, burr or rough edge is left anywhere on the link. The pins may therefore have a full bearing in the link when new, and the chain made from these links retains its accuracy a much greater time and wears more slowly than chains of ordinary type, and, in addition, is infinitely stronger.

The metal strip or bar is preferably dead soft when bent to the desired shape, and the links may be hardened by any approved process as may be necessary to produce the requisite wearing qualities.

I claim:

1. A link for drive chains consisting of a strip of metal bent upon itself to form pin loops, one end of the metal strip lying inside of the link thus formed, and the other end extending outwardly away from the link to form an attaching carrier.

2. A link for drive chains comprising a. flat strip of metal bent into two pin engaging loops, each pin loop consisting of a plurality of layers of metal, the ends of the metal strip overlying each other between the two pin loops, whereby the medial portion oi the loop contains more metal than the pin loops, a weld in the medial portion of the link holding the metal layers to ether, one end of the metal strip being s arply bent from the link thus forming an attachment carrier.

3. A link for drive chains comprising a strip of flat metal formed into loops for engaging pins, each loop consisting of a plurality of layers of metal having the flat sides in contact and the longitudinal edges parallel, the ends of the metal strip overlying each other, one end being on the outside of the link and the other being on the inside of the link, the end on the outside of the link having a sharp bend across the flat metal strip and extending from the link to form an attachment carrier.

EDGAR B. NICHOLS. 

